Conventional prior art mass market computing platforms include the well-known personal computer (PC), and a proliferation of known palmtop, laptop and mobile phone-type personal computers. Generally, markets for such machines fall into two categories, these being domestic or consumer, and corporate. A general requirement for a computing platform for domestic or consumer use is a relatively high processing power, Internet access features, and multi-media features for handling computer games.
On the other hand, for business use, there are a number of different proprietary computer platform solutions available aimed at organisations ranging from small businesses to multi-national organisations. In many of these applications, a server platform provides centralised data storage, and application functionality for a plurality of client stations. For business use, other key criteria are reliability, networking features and security features.
With the increase in commercial activity transacted over the Internet, known as “e-commerce”, there has been much interest in the prior art on enabling transactions between computing platforms, over the Internet. However, because of the potential for fraud and manipulation of electronic data, in such proposals, fully automated transactions with distant in the prior art on enabling transactions between computing platforms, over the Internet. However, because of the potential for fraud and manipulation of electronic data, in such proposals, fully automated transactions with distant unknown parties on a wide-spread scale as required for a fully transparent and efficient market place have so far been held back. The fundamental issue is one of trust between interacting computer platforms for the making of such transactions.
There have been several prior art schemes which are aimed at increasing the security and trustworthiness of computer platforms. Predominantly, these rely upon adding in security features at the application level. That is to say the security features are not embedded in the kernel of operating systems, and are not built into the fundamental hardware components of the computing platform. Although such prior art schemes go some way to improving the security of computer platforms, the levels of security and trustworthiness gained by prior art schemes may be considered insufficient to enable widespread application of automated transactions between computer platforms, and greater confidence in the trustworthiness of the underlying technology is thought to be required for many applications.
In the applicant's co-pending International Patent Application No. PCT/GB00/00528 entitled “Trusted Computing Platform” and filed on Feb. 15, 2000, the entire contents of which are incorporated herein by reference, there is disclosed a concept of a ‘trusted computing platform’ comprising a computing platform which has a ‘trusted component’ in the form of a built-in hardware and software component. Two computing entities each provisioned with such a trusted component may interact with each other with a high degree of ‘trust’. That is to say, where the first and second computing entities interact with each other the security of the interaction is enhanced compared to the case where no trusted component is present, because:                A user of a computing entity has higher confidence in the integrity and security of his/her own computer and in the integrity and security of the computer entity belonging to the other computing entity.        Each entity is confident that the other entity is in fact the entity which it purports to be.        Where one or both of the entities represent a party to a transaction, e.g. a data transfer transaction, because of the in-built trusted component, third party entities interacting with the entity have a high degree of confidence that the entity does in fact represent such a party.        The trusted component increases the inherent security of the entity itself, through verification and monitoring processes implemented by the trusted component.        The computer entity is more likely to behave in the way it is expected to behave.        
International Patent Application No. PCT/GB00/00528 describes a method of determining whether a target trusted platform is alive and trustworthy, by issuing an “integrity challenge ” and receiving an “integrity response”. This method has been further developed by the Trusted Computing Platform Alliance (TCPA), an industry consortium focussed on improving trust and security on computing platforms. In its version 1.0 of the Trusted Computing Platform Specifications, a clear direction is provided to industry that facilitates trust in computing platforms and environments. It defines a subsystem so that it may be trusted to operate as expected. The subsystem contains an isolated computing engine whose processes can be trusted because they cannot be altered. The specification also describes features that will enable a basic level of trust in a platform in order to be considered trustworthy by local users and by remote entities. In the TCPA specification, a trusted platform obtains a cryptographic identity that proves that the platform is a trusted platform. When a third party sends an integrity challenge (a nonce) to the platform, the platform appends a summary of integrity measurements to the nonce, then signs the concatenated data using the trusted identity. This functionality is provided by the TCPA command named QUOTE. The signed data returned by a QUOTE is used with other TCPA data to determine whether the platform will be trusted by the third party. Such determination is done by the third party, because the trustworthiness of a platform depends on the intended use of that platform, and only the third party is in a position to make that decision.
In the applicant's co-pending British Patent Application No. 0020441.2, filed on Aug. 18 2001 and entitled ‘Performance of a Service on a Computing Platform’, there is described a method of performing a service for a requestor on a computing platform, comprising the steps of the requestor providing to the computing platform a specification of the service to be performed, wherein the specification of the service establishes specified levels of trust for at least some of the processes in the service, the computing platform executing the service according to the specification and logging the performance of at least some of the processes for which a level of trust was specified, and providing the requestor with a log of the performance of the processes performed according to the specified levels of trust.
Thus, the disclosed method allows for the provision of evidence of satisfactory performance of services on a computing platform in response to an electronically received request. The service can be specified to the computing platform, and in addition to the results of the service (if these are required by the requester—these may be required elsewhere), the requestor is provided with evidence that the service has been satisfactorily performed by the computing platform.
While the methods described in the applicant's co-pending disclosures and the TCPA specification provide information that assists in determining whether a target platform may be considered trustworthy, none of them describe a method of indicating to a person that a target platform is considered trustworthy.